Medical image diagnostic apparatus

Abstract

According to one embodiment, medical image diagnostic apparatus includes a bed, a display, and processing circuitry. The bed movably supports a top plate. The display displays a setting window for setting an acquisition time of PET event data for each acquisition area. The processing circuitry sets an acquisition time for each acquisition area in response to a setting instruction of the acquisition time for each acquisition area. The acquisition area includes a unit acquisition area or a plurality of unit acquisition areas which overlap with each other with variable overlap ratio. The unit acquisition area corresponds to a coverage of a gamma ray detector. The processing circuitry adjusts the overlap ratio of at least one of two neighboring acquisition areas so that the boundary of the neighboring acquisition areas is set to a position designated by a user.

The invention claimed is: 
     
       1. A medical image diagnostic apparatus comprising:
 a bed that movably supports a top plate in a long axis direction; 
 a display that displays a setting window through which an acquisition time of PET event data is set for each of acquisition areas arranged in the long axis direction of the top plate; and 
 processing circuitry that:
 sets an acquisition time for each of the acquisition areas in response to a setting instruction of the acquisition time for each of the acquisition areas received through the setting window; 
 performs PET imaging for each of the acquisition areas in accordance with the set acquisition time, and acquires PET event data that represents the count of gamma rays emitted from a subject, and 
 generates a PET image based on the acquired PET event data, 
 
 wherein the acquisition areas each include a unit acquisition area or a plurality of unit acquisition areas which overlap with each other in the long axis direction with a variable overlap ratio, 
 each of the unit acquisition areas corresponds to a coverage of a gamma ray detector included in a PET gantry, and 
 the processing circuitry sets the plurality of acquisition areas arranged in the long axis direction and the acquisition time for each of the acquisition areas, and 
 when a user designates a given position of the set acquisition areas, the processing circuitry adjusts the overlap ratio of a first acquisition area set with a first acquisition time and including the given position of the acquisition areas or a second acquisition area adjacent to the first acquisition area and having a second acquisition time different than the first acquisition time so that a boundary between the first area and the second area matches the given position. 
 
     
     
       2. The medical image diagnostic apparatus according to  claim 1 , wherein:
 the processing circuitry sets, as an acquisition time, a level designated from among predetermined levels through an input device for each of the acquisition areas. 
 
     
     
       3. The medical image diagnostic apparatus according to  claim 2 , wherein:
 a value of each of the levels is independently set, or is set by multiplying a value of a level by a constant value. 
 
     
     
       4. The medical image diagnostic apparatus according to  claim 1 , wherein:
 the display displays an indicator of each of the acquisition areas included in the setting window in a color corresponding to the respective set acquisition times. 
 
     
     
       5. The medical image diagnostic apparatus according to  claim 1 , wherein:
 the processing circuitry adjusts an acquisition time of an overlap portion between the two neighboring acquisition areas to decrease a gap in acquisition time between the two neighboring acquisition areas. 
 
     
     
       6. The medical image diagnostic apparatus according to  claim 1 , wherein:
 the processing circuitry determines division of the acquisition areas and sets the acquisition times, thereafter the processing circuitry performs a positioning scan on the subject to acquire scan data, and generates a positioning image for the subject based on the scan data; and 
 the display displays the positioning image on the setting window, and displays the acquisition areas superimposed on the positioning image to adjust the division of the acquisition areas. 
 
     
     
       7. The medical image diagnostic apparatus according to  claim 1 , wherein:
 the processing circuitry performs filtering to the PET image, and reduces a gap in image quality between two neighboring acquisition areas which are different in acquisition time. 
 
     
     
       8. A medical image diagnostic apparatus comprising:
 a bed that movably supports a top plate in a long axis direction; 
 a PET gantry that performs PET imaging; 
 a CT gantry that performs CT imaging; 
 processing circuitry that:
 performs a positioning scan on a subject placed on the top plate by the PET gantry, while moving the top plate in the long axis direction, to acquire PET event data; and 
 sets an acquisition time for each of acquisition areas for an intermittent movement scan that performs the PET imaging to each of the acquisition areas by the PET gantry while intermittently moving the top plate in the long axis direction, based on the PET event data or a positioning image based on the PET event data, 
 
 wherein the processing circuitry extracts a brain area and a bladder area of the subject based on counts of the acquired PET event data, extracts each of the portions of the subject based on a distance between the brain and the bladder, identifies a count each of portions of the subject based on the acquired PET event data, and sets an acquisition area corresponding to respective portions of the subject and sets an acquisition time for each of the acquisition areas corresponding to respective portions of the subject in accordance with the count of the PET event data corresponding to said respective portions of the subject. 
 
     
     
       9. A medical image diagnostic apparatus comprising:
 a memory that stores an upper limit value of the count for each of portions of a subject; 
 a bed that movably supports a top plate in a long axis direction; and 
 processing circuitry that: 
 acquires count data that indicates a count of gamma rays emitted from respective portions of a body of the subject placed on the top plate, 
 sets an acquisition area corresponding to respective portions of the subject and sets an acquisition time for each of the acquisition areas corresponding to respective portions of the subject in accordance with the count data corresponding to said respective portions of the subject, and 
 controls the bed to intermittently move the top plate in the long axis direction in order to perform PET imaging on the subject, wherein the processing circuitry moves the top plate to a next position if the count reaches the upper limit value corresponding to an image target portion.